Re: MPEG1 MPEG2 layer3

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Re: MPEG1 MPEG2 layer3

george steeves
[hidden email]





I have a question for which I can find no definitive answer.  MPEG layer3
files are in two flavors MPEG1 and MPEG2.  I know this is true as the
Lame_enc.dll switches from MPEG2 to MPEG1 when the bit rate is increased
beyond 160kb/s.  I have read the source code and I know this is so.  Is this
only true of the Lame encoder or only true of the lame_enc.dll.  What is the
difference?  Which is better? Why?


--
George Steeves
Box 111
Gilboa, NY 12076
Web Site: georgesteeves.com
607-588-6324
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Re: MPEG1 MPEG2 layer3

Ruckert Martin
Thinks to keep apart: Version and Layer

MPEG Version 1 specifies 3 Layers 1,2, and 3
within Version 1 we have a restricted selection of three
sample rates: 32kHz, 44.1kHz or 48kHz
and bitrates:
32kBit/s to 448kBit/s for layer 1
32kBit/s to 384kBit/s for layer 2 and
32kBit/s to 320kBit/s for layer 3

MPEG Version 2 introduces new
sample rates: 16kHz, 22.05kHz or 24kHz
with different bitrates:
32kBit/s to 256kBit/s for layer 1
8kBit/s to 160kBit/s for layer 2 and 3

There is an extension without a ISO Standard called MPEG version 2.5
again with different
sample rates: 8kHz, 11.025kHz or 12kHz
with different bitrates:
8kBit/s to 64kBit/s for layer 3

So you see: you have to switch the version, if the sample rate is changing.
You have to switch the layer if the bitrate is changing.
Now to the question:
 From the above, you see, that while encoding a version 2 stream with one of the
version 2 sample rates in layer 2, you can use only bitrates between 8kBit and 160kBit.
If the bitrate has to increase beyond 160kBit, you can not switch to MPEG version 1,
(because the sample rate has not changed), but you must switch to layer 1, because
in layer 1 you can use bitrates up to 256kBit/s.
On the other hand you must switch back, if the bitrate is below 32kBit.

Now which is better: typically layer 3 gives you a more compact encoding
therefore smaller bitrates are sufficient. So go with layer 3. The
version depends on the sample rate. Higher sample rates are typicaly better
but not as compact to encode then lower sample rates. lame will automatically
downsample in needed. leave it to lame to decide.


Yours
   Martin Ruckert

PS: these and other such details, you find in "Understanding MP3", Springer Verlag.

george steeves wrote:

> [hidden email]
>
>
>
>
>
> I have a question for which I can find no definitive answer.  MPEG layer3
> files are in two flavors MPEG1 and MPEG2.  I know this is true as the
> Lame_enc.dll switches from MPEG2 to MPEG1 when the bit rate is increased
> beyond 160kb/s.  I have read the source code and I know this is so.  Is this
> only true of the Lame encoder or only true of the lame_enc.dll.  What is the
> difference?  Which is better? Why?
>
>


--
-------------------------------------
Prof.Dr.Martin Ruckert
Munich University of Applied Sciences
FB07 Mathematics and Computer Science
Lothstrasse 34
D-80335 Munich
GERMANY
_______________________________________________
mp3encoder mailing list
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Re: MPEG1 MPEG2 layer3

george steeves
So this being so it would seem that 160kb/s MPEG2 is the best bit rate and
format for layer 3 as MPEG2 is superior to MPEG1??

George


On 11/22/06, Ruckert Martin <[hidden email]> wrote:

>
> Thinks to keep apart: Version and Layer
>
> MPEG Version 1 specifies 3 Layers 1,2, and 3
> within Version 1 we have a restricted selection of three
> sample rates: 32kHz, 44.1kHz or 48kHz
> and bitrates:
> 32kBit/s to 448kBit/s for layer 1
> 32kBit/s to 384kBit/s for layer 2 and
> 32kBit/s to 320kBit/s for layer 3
>
> MPEG Version 2 introduces new
> sample rates: 16kHz, 22.05kHz or 24kHz
> with different bitrates:
> 32kBit/s to 256kBit/s for layer 1
> 8kBit/s to 160kBit/s for layer 2 and 3
>
> There is an extension without a ISO Standard called MPEG version 2.5
> again with different
> sample rates: 8kHz, 11.025kHz or 12kHz
> with different bitrates:
> 8kBit/s to 64kBit/s for layer 3
>
> So you see: you have to switch the version, if the sample rate is
> changing.
> You have to switch the layer if the bitrate is changing.
> Now to the question:
> From the above, you see, that while encoding a version 2 stream with one
> of the
> version 2 sample rates in layer 2, you can use only bitrates between 8kBit
> and 160kBit.
> If the bitrate has to increase beyond 160kBit, you can not switch to MPEG
> version 1,
> (because the sample rate has not changed), but you must switch to layer 1,
> because
> in layer 1 you can use bitrates up to 256kBit/s.
> On the other hand you must switch back, if the bitrate is below 32kBit.
>
> Now which is better: typically layer 3 gives you a more compact encoding
> therefore smaller bitrates are sufficient. So go with layer 3. The
> version depends on the sample rate. Higher sample rates are typicaly
> better
> but not as compact to encode then lower sample rates. lame will
> automatically
> downsample in needed. leave it to lame to decide.
>
>
> Yours
>   Martin Ruckert
>
> PS: these and other such details, you find in "Understanding MP3",
> Springer Verlag.
>
> george steeves wrote:
> > [hidden email]
> >
> >
> >
> >
> >
> > I have a question for which I can find no definitive answer.  MPEG
> layer3
> > files are in two flavors MPEG1 and MPEG2.  I know this is true as the
> > Lame_enc.dll switches from MPEG2 to MPEG1 when the bit rate is increased
> > beyond 160kb/s.  I have read the source code and I know this is so.  Is
> this
> > only true of the Lame encoder or only true of the lame_enc.dll.  What is
> the
> > difference?  Which is better? Why?
> >
> >
>
>
> --
> -------------------------------------
> Prof.Dr.Martin Ruckert
> Munich University of Applied Sciences
> FB07 Mathematics and Computer Science
> Lothstrasse 34
> D-80335 Munich
> GERMANY
> _______________________________________________
> mp3encoder mailing list
> [hidden email]
> https://minnie.tuhs.org/mailman/listinfo/mp3encoder
>



--
George Steeves
Box 111
Gilboa, NY 12076
Web Site: georgesteeves.com
607-588-6324
_______________________________________________
mp3encoder mailing list
[hidden email]
https://minnie.tuhs.org/mailman/listinfo/mp3encoder
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Re: MPEG1 MPEG2 layer3

Ruckert Martin
Sorry, but No.
MPEG Version 2 (short MPEG2) specifies the Low Frequency extensions
to MPEG Version 1. MPEG2 is supperior in terms of low bitrates
and high compression, it is inferior in respect to quality.
If quality matters, use MPEG Version 1 Layer 3.
Yours
    Martin Ruckert

george steeves wrote:

> So this being so it would seem that 160kb/s MPEG2 is the best bit rate and
> format for layer 3 as MPEG2 is superior to MPEG1??
>
> George
>
>
> On 11/22/06, Ruckert Martin <[hidden email]> wrote:
>
>>Things to keep apart: Version and Layer
>>
>>MPEG Version 1 specifies 3 Layers 1,2, and 3
>>within Version 1 we have a restricted selection of three
>>sample rates: 32kHz, 44.1kHz or 48kHz
>>and bitrates:
>>32kBit/s to 448kBit/s for layer 1
>>32kBit/s to 384kBit/s for layer 2 and
>>32kBit/s to 320kBit/s for layer 3
>>
>>MPEG Version 2 introduces new
>>sample rates: 16kHz, 22.05kHz or 24kHz
>>with different bitrates:
>>32kBit/s to 256kBit/s for layer 1
>>8kBit/s to 160kBit/s for layer 2 and 3
>>
>>There is an extension without an ISO Standard called MPEG version 2.5
>>again with different
>>sample rates: 8kHz, 11.025kHz or 12kHz
>>with different bitrates:
>>8kBit/s to 64kBit/s for layer 3
>>
>>So you see: you have to switch the version, if the sample rate is
>>changing.
>>You have to switch the layer if the bitrate is changing.
>>Now to the question:
>>From the above, you see, that while encoding a version 2 stream with one
>>of the
>>version 2 sample rates in layer 2, you can use only bitrates between 8kBit
>>and 160kBit.
>>If the bitrate has to increase beyond 160kBit, you can not switch to MPEG
>>version 1,
>>(because the sample rate has not changed), but you must switch to layer 1,
>>because
>>in layer 1 you can use bitrates up to 256kBit/s.
>>On the other hand you must switch back, if the bitrate is below 32kBit.
>>
>>Now which is better: typically layer 3 gives you a more compact encoding
>>therefore smaller bitrates are sufficient. So go with layer 3. The
>>version depends on the sample rate. Higher sample rates are typicaly
>>better
>>but not as compact to encode then lower sample rates. lame will
>>automatically
>>downsample in needed. leave it to lame to decide.
>>
>>
>>Yours
>>  Martin Ruckert
>>
>>PS: these and other such details, you find in "Understanding MP3",
>>Springer Verlag.
>>
>>george steeves wrote:
>>
>>>[hidden email]
>>>
>>>
>>>
>>>
>>>
>>>I have a question for which I can find no definitive answer.  MPEG
>>
>>layer3
>>
>>>files are in two flavors MPEG1 and MPEG2.  I know this is true as the
>>>Lame_enc.dll switches from MPEG2 to MPEG1 when the bit rate is increased
>>>beyond 160kb/s.  I have read the source code and I know this is so.  Is
>>
>>this
>>
>>>only true of the Lame encoder or only true of the lame_enc.dll.  What is
>>
>>the
>>
>>>difference?  Which is better? Why?
>>>
>>>
>>
>>
>>--
>>-------------------------------------
>>Prof.Dr.Martin Ruckert
>>Munich University of Applied Sciences
>>FB07 Mathematics and Computer Science
>>Lothstrasse 34
>>D-80335 Munich
>>GERMANY
>>_______________________________________________
>>mp3encoder mailing list
>>[hidden email]
>>https://minnie.tuhs.org/mailman/listinfo/mp3encoder
>>
>
>
>
>


--
-------------------------------------
Prof.Dr.Martin Ruckert
Munich University of Applied Sciences
FB07 Mathematics and Computer Science
Lothstrasse 34
D-80335 Munich
GERMANY
_______________________________________________
mp3encoder mailing list
[hidden email]
https://minnie.tuhs.org/mailman/listinfo/mp3encoder
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Re: MPEG1 MPEG2 layer3

tech list
Layer is typically not changed, unless you specify it.
For higher bit rates/better quality sound, stick to MPEG-1.

On 11/23/06, Ruckert Martin <[hidden email]> wrote:

>
> Sorry, but No.
> MPEG Version 2 (short MPEG2) specifies the Low Frequency extensions
> to MPEG Version 1. MPEG2 is supperior in terms of low bitrates
> and high compression, it is inferior in respect to quality.
> If quality matters, use MPEG Version 1 Layer 3.
> Yours
>     Martin Ruckert
>
> george steeves wrote:
> > So this being so it would seem that 160kb/s MPEG2 is the best bit rate
> and
> > format for layer 3 as MPEG2 is superior to MPEG1??
> >
> > George
> >
> >
> > On 11/22/06, Ruckert Martin <[hidden email]> wrote:
> >
> >>Things to keep apart: Version and Layer
> >>
> >>MPEG Version 1 specifies 3 Layers 1,2, and 3
> >>within Version 1 we have a restricted selection of three
> >>sample rates: 32kHz, 44.1kHz or 48kHz
> >>and bitrates:
> >>32kBit/s to 448kBit/s for layer 1
> >>32kBit/s to 384kBit/s for layer 2 and
> >>32kBit/s to 320kBit/s for layer 3
> >>
> >>MPEG Version 2 introduces new
> >>sample rates: 16kHz, 22.05kHz or 24kHz
> >>with different bitrates:
> >>32kBit/s to 256kBit/s for layer 1
> >>8kBit/s to 160kBit/s for layer 2 and 3
> >>
> >>There is an extension without an ISO Standard called MPEG version 2.5
> >>again with different
> >>sample rates: 8kHz, 11.025kHz or 12kHz
> >>with different bitrates:
> >>8kBit/s to 64kBit/s for layer 3
> >>
> >>So you see: you have to switch the version, if the sample rate is
> >>changing.
> >>You have to switch the layer if the bitrate is changing.
> >>Now to the question:
> >>From the above, you see, that while encoding a version 2 stream with one
> >>of the
> >>version 2 sample rates in layer 2, you can use only bitrates between
> 8kBit
> >>and 160kBit.
> >>If the bitrate has to increase beyond 160kBit, you can not switch to
> MPEG
> >>version 1,
> >>(because the sample rate has not changed), but you must switch to layer
> 1,
> >>because
> >>in layer 1 you can use bitrates up to 256kBit/s.
> >>On the other hand you must switch back, if the bitrate is below 32kBit.
> >>
> >>Now which is better: typically layer 3 gives you a more compact encoding
> >>therefore smaller bitrates are sufficient. So go with layer 3. The
> >>version depends on the sample rate. Higher sample rates are typicaly
> >>better
> >>but not as compact to encode then lower sample rates. lame will
> >>automatically
> >>downsample in needed. leave it to lame to decide.
> >>
> >>
> >>Yours
> >>  Martin Ruckert
> >>
> >>PS: these and other such details, you find in "Understanding MP3",
> >>Springer Verlag.
> >>
> >>george steeves wrote:
> >>
> >>>[hidden email]
> >>>
> >>>
> >>>
> >>>
> >>>
> >>>I have a question for which I can find no definitive answer.  MPEG
> >>
> >>layer3
> >>
> >>>files are in two flavors MPEG1 and MPEG2.  I know this is true as the
> >>>Lame_enc.dll switches from MPEG2 to MPEG1 when the bit rate is
> increased
> >>>beyond 160kb/s.  I have read the source code and I know this is so.  Is
> >>
> >>this
> >>
> >>>only true of the Lame encoder or only true of the lame_enc.dll.  What
> is
> >>
> >>the
> >>
> >>>difference?  Which is better? Why?
> >>>
> >>>
> >>
> >>
> >>--
> >>-------------------------------------
> >>Prof.Dr.Martin Ruckert
> >>Munich University of Applied Sciences
> >>FB07 Mathematics and Computer Science
> >>Lothstrasse 34
> >>D-80335 Munich
> >>GERMANY
> >>_______________________________________________
> >>mp3encoder mailing list
> >>[hidden email]
> >>https://minnie.tuhs.org/mailman/listinfo/mp3encoder
> >>
> >
> >
> >
> >
>
>
> --
> -------------------------------------
> Prof.Dr.Martin Ruckert
> Munich University of Applied Sciences
> FB07 Mathematics and Computer Science
> Lothstrasse 34
> D-80335 Munich
> GERMANY
> _______________________________________________
> mp3encoder mailing list
> [hidden email]
> https://minnie.tuhs.org/mailman/listinfo/mp3encoder
>
_______________________________________________
mp3encoder mailing list
[hidden email]
https://minnie.tuhs.org/mailman/listinfo/mp3encoder